Force Description
Overview
The framework for describing fundamental forces: Newton (gravity), Maxwell (electromagnetism), Yang–Mills (gauge forces). Unification remains an open goal.
Era: 1687–1954
Proposed at: Cambridge, UK / Princeton, USA
Formal structure
Domain: Field φ(x); spacetime x ∈ M; gauge group G
L = L_kin(φ) + L_gauge(A) + L_int(φ,A); F_μν = ∂_μ A_ν − ∂_ν A_μ + [A_μ,A_ν]
Constraints: Gauge invariance: L[A^g] = L[A]; renormalizability
Objective: Unify forces; predict couplings; Standard Model